The following SMS server ports are optional.
| Port | Service | From | To | Description |
| 389/TCP/UDP | LDAP non-SSL | SMS server | AD server | SMS AD LDAP authentication |
| 636/TCP/UDP | LDAP over SSL | SMS server | AD server | SMS AD LDAP over SSL authentication |
| 3306/TCP | Database | SMS server | Any | External database access |
| External server | External replication | |||
| 53/TCP/UDP | DNS | SMS server | Name server | Name resolution |
| 443/TCP | URL Threat Analysis | SMS server | DD Analyzer | Send URL data from the SMS to the DD Analyzer. |
| 111/TCP/UDP | NFS | SMS server | File server | Report export, database backup |
| 369/TCP/UDP | ||||
| 2039/TCP/UDP | ||||
| 123/UDP | NTP | SMS server | NTP server (time source) | Time synchronization from external NTP server |
| 1812/UDP | RADIUS | SMS server | RADIUS server | SMS user authentication |
| 49/TCP | TACACS+ | SMS server | TACACS+ server | SMS user authentication |
| 137/TCP/UDP | Samba | SMS server | File server | Report export, database backup |
| 138/TCP/UDP | ||||
| 139/TCP/UDP | ||||
| 1512/TCP/UDP | ||||
| 25/TCP | SMTP | SMS server | Mail server | Email notifications such IPS events, Responder |
| 514/UDP | Syslog | SMS server | Syslog server | SMS alerts, audit and system logs |